1. Understanding Fuel Usage for Energy in Sport Nutrition For Sports Performance

2. Lesson Objectives To identify the different fuels the body uses and when To identify the effects of exercise duration on fuel usage To identify the fuels used in aerobic and anaerobic activity To identify fuels used in Training phase (pre- season) Pre-competition Competition Post-competition Off-season

3. How Does my Body Decide Which Fuel to Use ? Type, duration and intensity of exercise Fitness level and training programme Diet and nutritional status

4. Training Intensity Exercise Intensity LowHigh 0% 100% FAT MUSCLE GLYCOGEN

5. Training Intensity Low (Aerobic) High % fat - low % carbs Medium (Aerobic) High % carbs – low % fat High (Anaerobic) 100% carbs – 0% fat

6. Effects of Duration Aerobic training Continued aerobic exercise uses more and more fat and less and less CHO’s.

7. Effects of Duration Time (mins) 0 0% 100% FAT MUSCLE GLYCOGEN 75 6045 30 15 Muscle Glycogen Fat

8. Duration & Glycogen Stores Glycogen cannot supply energy indefinitely. 90-180 mins of endurance exercise at 60-80% of maximum. 30-45 mins of high intensity anaerobic activities. 45-90 mins endurance/anaerobic activity

9. Aerobic and Anaerobic Exercise Anaerobic – High intensity, short duration. Body must produce energy very rapidly without oxygen. Activity can be kept up for only brief period.

10. Anaerobic Activity CHO’s must be converted into energy rapidly in order to meet sudden high demand. Glucose bypasses usual oxygen pathway to save time. Glucose is only partially broken down. 38 molecules of ATP per glucose molecule aerobic, only 2 ATP’s when anaerobic. Large amounts of glucose must be broken down therefore stores dwindle quickly.

11. Aerobic Activity Glucose is completely broken down. 1 molecule of glucose can create 38 ATP’s 20 times more efficient than anaerobic. Aerobic can also use fat as well as glycogen. 1 fatty acid produces between 80-200 ATP. Can only be broken down under aerobic conditions – low energy demands, slow production.

12. Anaerobic Energy System GLYCOGEN GLUCOSE LACTIC ACID ATP ENERGY +

13. Aerobic Energy System GLYCOGEN FAT GLUCOSE FATTY ACIDS + OXYGEN +OXYGEN 38 MOLECULES 80-200 MOLECULES ATP ATP ENERGY

14. The Phospho-Creatine System (PC System) Regenerates ATP for fast sudden burst of activity lasting few seconds – throw, jump, lift. PC is limited and can last only a few seconds. After this energy is provided by glycogen or fats.

15. Training Considerations Training phase (pre- season) Pre-competition Competition Post-competition Off-season

16. Training Phase 60-70% Carbohydrate Good opportunity to eat complex CHO’s as they have higher nutritional value than refined simple CHO’s (confectionary, soft drinks). May increase protein % slightly if bulking up / building muscle. Activity will aid weight management, but a slight drop in CHO may occur depending on metabolic rate.

17. Pre Competition Pre-exercise carbs can help you maintain higher blood sugar levels, delay fatigue and improve endurance. Complex carbs 2-4 hours before (Storage) Simple carbs 5-30 mins before you exercise. Examples: 2-3 bananas 3oz dried fruit Chocolate bar 1 pint isotonic sports drink

18. Examples of Successful Pre- Competition Foods Cornell University. Tri-athletes who ate 2-3 bananas immediately before a cycle trial were able to keep going 16-18 mins longer than those who ate nothing. Ohio State University. Gave cyclists a carb drink (sugar) 1 hour before competition. Performance improved by 12.5% compared with those who drank water.

19. Post-Competition 2 hour window where muscles will store glycogen quicker than usual – the ‘golden hour’ after competition Simple CHO’s immediately after competition. Complex CHO’s within 2 hours – large quantity to replace stores.

20. Effects of Diet on Recovery 0 20 40 80 100 120 60 1 2 3 4 2 hour training bouts 70% Carbs diet 40% Carbs diet Days Muscle glycogen level

21. Summary Aerobic vs Anaerobic fuel usage Effect of continued aerobic activity is to utilise more fat as fuel Different factors affecting how fuel is used in the body Fuels used in different phases of competition will vary – but extremely important Research being undertaken